1. Field of the Invention
The present invention, in general relates to wheeled vehicles and, more particularly, to mobile types of devices that are powered by hand.
Hand powered mobile devices are generally known. For example, hand-powered rail carts for use on railroad tracks that have a central pivotal bar that is alternately raised and lowered are well known devices that can be powered by one or more persons simultaneously, but they are not practical for use on the street, especially by an individual operator. There are a number of reasons why these, and other prior art types of devices, are not well suited for individual use or for use on the street.
One such reason is because they tend to have large, cumbersome mechanisms and, as such, do not lend themselves well for use with smaller and lighter types of vehicles, for example, with two or three-wheeled types of scooters.
Recent developments in lightweight and durable materials have contributed to a great variety of small, folding types of scooters. These include two-wheeled types of mobile devices that are propelled by an individual standing on a platform of the scooter and kicking with one leg to propel the device.
This type of a kicking impulse makes for limited and inefficient use of the strengths of the individual and furthermore, because the individual is likely to use only a predominant leg for kicking, it fosters an uneven pattern of physical development (i.e., exercise).
It is desirable to be able to use the arms and hands of the individual to supply a motive force for a smaller, scooter-like, vehicle yet no lightweight and effective mechanism currently exists for doing so.
It is also desirable to use the muscle groups in the arms to supply this force. The arms have substantial muscle groups that, if an ergonomic system were to well utilize them, are well adapted to propel a scooter-like type of a vehicle.
Furthermore, doing so would strengthen the upper body while simultaneously providing a practical vehicle for short distance commuting.
Furthermore, prior types of hand powered devices do not provide a method for synchronizing the motion of both hands (and arms) of the user so that an alternating pushing and pulling motion, each arm at a time and in opposite relation to the other, would occur. Such a synchronized pattern of movement is optimally desired to provide the motive impulse.
A synchronized motion that ensures a particular relative position of one hand alternating back and forth when compared to the other is optimum for both power generation and also for comfort.
It is preferable to set up a routine whereby a recurrent pattern of motion occurs. This is one reason why pedaling a bicycle is so common. It involves a recurrent pattern of motion and that creates familiarity and the familiarity, in turn, fosters user comfort and confidence in the process and product.
Also, kicking a scooter provides a motive force (i.e., an impulse) and then the scooter coasts for a predetermined period of time until another kick can be accomplished. In other words the motive force is intermittent. It is desirable to be able to supply a more continuous motive force (i.e., one with a greater duty cycle whereby motive power is being supplied most of the time) to a scooter-like vehicle.
There is also a need for being able to change the gear ratios of a hand-powered vehicle. A high gear ratio is helpful when initially beginning to move, going up a hill, it is desirable to go slowly, or when carrying a heavy load. A medium gear ratio is helpful after beginning to move, going up a slight incline or on level ground, when it is desirable to go at a medium speed, or when carrying a moderate load. A high gear ratio is helpful after attaining a brisk speed, going up down slight incline or on level ground, when it is desirable to go at a high speed, or when carrying a light load. Clearly, no one speed can optimally satisfy all of the above conditions.
There is also a need to brake and slow down on demand a hand-powered vehicle. Clearly, this would provide optimum safety.
There is also a need to provide as lightweight as possible a hand-powered vehicle. Meshing types of gears (that mesh together) and racks are solid structures that add considerable weight and bulk whereas chains and gears that are driven off of the chains, as in a conventional bicycle, optimize the transfer of power at minimum weight.
Additionally, there is a need for an alternate source of power that can be integrated for use with a hand-powered vehicle. For example, a small gasoline or electric motor and battery, if it could be used to supplement human powered force would be a desirable addition.
Accordingly, there exists today a need for a hand-powered vehicle that is lightweight, effectively transfers power derived from the hand and arm motion of the user into rotary motion that is used as a motive force, provides this force more evenly and continuously than by kicking, includes a variety of gears, includes a brake, is adapted for a supplemental source of power, and which provides a positive and predictable relationship between two members that are alternately moved back and forth by the user.
Clearly, such an apparatus would be a useful and desirable device.
2. Description of Prior Art
Hand-powered vehicles are, in general, known. For example, the following patents describe various types of these devices:                U.S. Pat. No. 6,352,274 to Redman, March, 2002;        U.S. Pat. No. 6,080,088 to Petersen et al., Jun. 27, 2000;        U.S. Pat. No. 5,653,663 to McCahon, August, 1997;        U.S. Pat. No. 5,050,864 to Pertramer, Sep. 24, 1991;        U.S. Pat. No. 5,007,655 to Hanna, Apr. 16, 1991;        U.S. Pat. No. 4,960,286 to Henson, Oct. 2, 1990;        U.S. Pat. No. 4,861,055 to Jones, Aug. 29, 1989;        U.S. Pat. No. 4,460,190 to Speiss, July, 1984;        U.S. Pat. No. 4,189,166 to Lindsey, Feb. 19, 1980;        U.S. Pat. No. 2,085,657 to Heisdorf, Jun. 29, 1937;        U.S. Pat. No. 1,735,665 to Ashby, Nov. 12, 1929;        U.S. Pat. No. 1,455,124 to Swinland, May 15, 1923;        U.S. Pat. No. 946,280 to Slotkin, January, 1910;        U.S. Pat. No. 926,131 to McGowan, Jun. 29, 1909;        U.S. Pat. No. 843,646 to Vogel, February, 1907;        U.S. Pat. No. 577,572 to Cross, Feb. 23, 1897;        U.S. Pat. No. 435,665 to Minnix, September, 1890; and        Japanese document number 4-243681 to Ishi, August, 1992.        
While the structural arrangements of the above described devices, at first appearance, have similarities with the present invention, they differ in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior devices.